title: Alpha-aminoisobutyric acid loss by rat small intestine: role of intestinal site and luminal contents.
abstract: Loss of amino acid into the lumen may be important in diarrheal states. Labeled alpha-aminoisobutyric acid (AIB) was given parenterally, and concentration gradients developed between lumen, intestinal tissue and plasma. After 24 h, we measured AIB loss into the intestinal lumen by recirculating isolated segments in situ under conditions of either net water absorption or net water secretion. Final 14C-AIB concentrations in intestinal tissue were 200-800 times that of lumen, 6--15 times that of serum. Despite increased total 14C-AIB loss during net water secretion, and based on the low luminal 14C-AIB concentrations, the contribution of amino acid loss to fecal nitrogen during osmotic diarrhea appears to be minimal.
mesh_terms: D000621:Aminoisobutyric Acids / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D001834:Body Water / Q000378:metabolism; D003967:Diarrhea / Q000378:metabolism; D004386:Duodenum / Q000378:metabolism; D007082:Ileum / Q000378:metabolism; D007421:Intestine, Small / Q000378:metabolism*; D007583:Jejunum / Q000378:metabolism; D008297:Male; D008353:Mannitol / Q000494:pharmacology; D010477:Perfusion; D051381:Rats; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D000621:Aminoisobutyric Acids; D008353:Mannitol; D012965:Sodium Chloride